ECC memory

[rallynavvie]

I was browsing around my BIOS looking at settings the other day and noticed my memory settings. The ECC option was disabled. I don't remember disabling it anytime so I must have never enabled it. What are the consequences of enabling it? Does the error correcting function interfere with anything (i.e. compatability issues with programs) or slow anything down? I'd rather get some information first before turning it on and wrecking something. I've never had ECC RAM in a computer before so it's sorta new to me as to what all it can do.

[SaSi]

Some memory DIMMS/SIMMS/RIMMS come with extra parity bits in the memory chip arrays. It's used to check the memory state and identify bad bytes. It used to be common in the old days (1988~1992) and cost reduction along with improved RAM quality eliminated this.

Servers tend to use ECC RAM, some with the normal +1 parity bit others require +2 bits to do some sort of error correction rather than just lock-up.

If your PC doesn't have ECC memory (best bet is it doesn't) you will not be able to enable the option.

On ECC RAM configured systems, there is a 5-6% penalty in performance due to the ECC algorithms being active. Other than that, there is no compatibility issue.

A piece of advice: Don't play with the BIOS settings if you don't understand them. If you can' resist carefully note the current ones down for reference, FIRST make sure you find the hot-key combination that during boot restores a fail-safe configuration (sometimes it's the INS key or the F11 key) by reading the M/B manual. AFTER you've done that, you can play freely. And don't change more than a setting you don't understand at a time. Otherwise you'll get lost.

[Gazorgan]

Don't enable it unless you are 100% sure you have ECC RAM. You will have to reset your BIOS manually if you are wrong (the reset jumper, power on, then off and reset the jumper).

[rallynavvie]

Like I said, I've never owned a PC with ECC RAM before, that doesn't mean I know nothing of the rest of the settings in the BIOS

I know absolutely that the RAM in there is ECC. It's the only stuff that works with the ultra-finicky Tyan 2460 I've got right now. The only thing I worry about is the two different manufacturers of RAM I've got in there (Micron and Kingston 512MB sticks) not working well with each other with ECC enabled.

Will I even notice the small performance loss with my dual processor system and the 1GB of RAM? What are the performance benefits of having the ECC enabled?

[vitualis]

Read the above posts.

There is NO PERFORMANCE BENEFIT in having ECC enabled. There is in fact a performance hit.

ECC RAM is used basically in servers where stability is extremely important.

Regards.

[rallynavvie]

So the "performance benefit" is stability in server applications

Would the error-checking algorithms help at all with video applications as far as losing frames, bitmapping things, loss during capture, etc? I've had it off this long and things have worked OK so I didn't plan on changing that (don't fix it if it ain't broke) but am just learning more about what it can do.

Thanks for the replies!

[vitualis]

Would the error-checking algorithms help at all with video applications as far as losing frames, bitmapping things, loss during capture, etc? I've had it off this long and things have worked OK so I didn't plan on changing that (don't fix it if it ain't broke) but am just learning more about what it can do.

Basically no.

Regards.